<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>

<body>
    <canvas id="example"></canvas>
    <button id="run">运动</button>
    <button id="pause">停止</button>
    <button id="clear">清除</button>
</body>

</html>